The present invention relates to a control method and apparatus for an automobile air conditioning system, and more particularly to an electric control method and apparatus for an automobile air conditioning system in which an electromagnetic clutch mechanism is provided to connect a refrigerant compressor for an evaporator with a prime mover of the automobile.
In such a conventional electric control apparatus, it is desirable that while cooling ability of the air conditioning system is only partly utilized to condition the air in a passenger compartment of the automobile, the clutch mechanism is deenergized to disconnect the compressor from the prime mover so as to avoid undesired output power losses of the prime mover during travel of the automobile.